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Quarterly Journal of Microscopical Science, Vol s2-74, 321-360, Copyright © 1931 by Company of Biologists
1 Assistant Lecturer in Zoology in the University of Leeds
(1) The main features of the anatomy, histology, and development of the larval gut are described.
(2) The fore-gut is divisible into pharynx, oesophagus, crop, oesophageal valve, and anterior imaginal ring, or as here called, anterior interstitial ring. Details of the structure of each part are given, including an account of the musculature.
(3) The growth of the fore-gut is then traced and it is shown that increase in size is accompanied by increase in size of the constituent cells. Only in the interstitial ring does cell division occur after hatching.
(4) A considerable degree of histological differentiation is only to be observed after the commencement of feeding.
(5) The larval development of the mid-gut has been described in my previous paper (vide Bibliography).
(6) Evidence is presented for regarding the peritrophic membrane as entirely derived from the mid-gut.
(7) The hind-gut is then described as consisting of posterior interstitial ring (posterior imaginal ring), ileum, anterior sphincter region, colon, posterior sphincter region, anterior rectum and posterior rectum. The musculature of both fore-gut and hindgut is shown to be based on a radially symmetrical system of sixes.
(8) The growth principles of the hind-gut are essentially similar to those of the fore-gut.
(9) Evidence is presented to suggest an endodermal derivation for the malpighian tubules.
